This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 2001-055212, filed Feb. 28, 2001, the entire contents of which are incorporated herein by reference.
1. Field of the Invention
The present invention relates to a radio communications module to be mounted on a system board. The invention also relates to an electronic apparatus, such as a portable computer or a portable information tool, which incorporates the radio communications module.
2. Description of the Related Art
Recently, various electronic apparatuses, each incorporating a radio communications module such as Bluetooth (trademark) or wireless LAN, have become available. An electronic apparatus of this type comprises a housing that contains the radio communications module. The housing incorporates a system board. The system board has a mounting region, on which the first interface connector is mounted.
The radio communications module comprises a circuit board that can process radio signals. The circuit board has a connector surface that opposes the mounting region of the system board. On the connector surface, the second interface connector and an antenna connector are provided. The second interface connector is coupled to the first interface connector. The first and second connectors connect the radio communications module to the system board. The antenna connector is electrically connected to the RF circuit provided on the circuit board. An antenna cable connects the antenna connector to an antenna element. The node of the antenna connector and the antenna cable lies between the circuit board and the system board.
To determine the RF characteristics of the radio communications module, the module must be electrically connected to the system board. To this end, the antenna cable is removed from the antenna connector, and then the antenna connector is electrically disconnected from the RF circuit on the circuit board, and finally the test probe is connected to the antenna connector. After the RF characteristics of the module are determined, the antenna cable must be connected to the antenna connector.
The antenna connector opposes the mounting region of the system board, spaced a very short distance from the system board. Therefore, the antenna cable cannot be removed from the antenna connector unless the radio communications module is disconnected from the system board. Nor can the test probe contact the antenna connector if the module is disconnected from the system board. To determine the RF characteristics of the radio communications module, it is necessary to decompose the housing and, then, remove the module from the system board.
Obviously, it takes much time and labor to determine the RF characteristics of the radio communications module. The RF characteristics of the module cannot be determined with high efficiency.
A first object of the present invention is to provide a radio communications module that can be electrically tested by using a test probe, both reliably and efficiently.
A second object of the invention is to provide an electronic apparatus that incorporates a radio communications module of the type mentioned above.
To achieve the first object, a radio communications module according to a first aspect of the invention comprises: a circuit board which processes radio signals and which has a first surface and a second surface opposite to the first surface, the first surface opposing a system board;
a connection section which is arranged on the first surface of the circuit board and which is to be electrically connected to the system board;
an antenna connector which is arranged on the second surface of the circuit board and to which an antenna cable extending from an antenna element for achieving radio communication is to be electrically connected; and
a test terminal which is arranged on the second surface of the circuit board so as to measure a characteristic of the circuit board.
The test terminal faces away from the system board while the circuit board remains electrically connected to the system board. The test terminal would not lie between the circuit board and the system board. A test probe can therefore be brought into contact with the test terminal, without removing the circuit board from the system board. This makes it easy to determine the electrical properties of the radio communications module.
To attain the second object, an electronic apparatus according to a second aspect of the invention comprises: a housing which has an outer wall having a through hole; a system board which is incorporated in the housing and which has a mounting surface that opposes the outer wall; and a radio communications module which is mounted on the mounting surface of the system board. The module includes: a circuit board which processes radio signals and which has a first surface and a second surface, the first surface opposing the mounting surface, and the second surface being opposite to the first surface and opposing the outer wall; a connection section which is arranged on the first surface of the circuit board and which is to be electrically connected to the system board; an antenna connector which is arranged on one of the first surface and second surface of the circuit board and to which an antenna cable extending from an antenna element for achieving radio communication is to be electrically connected; and a test terminal which is arranged on the second surface of the circuit board, which is aligned with the through hole of the outer wall and to which a test probe inserted into the housing via the through hole is to be connected removably.
In the electronic apparatus, the test terminal faces away from the system board while the circuit board remains electrically connected to the system board. The test terminal would not lie between the circuit board and the system board. Additionally, the test probe can contact the test terminal when it is inserted into the housing via the through hole, because the test terminal is aligned with the through hole made in the outer wall.
Hence, the electrical characteristics of the radio communications module can be determined, without removing the module from the system board or decomposing the housing.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.